吸管法测定抗生素生物活性研究

以大蒜素对土壤细菌、真菌的敏感性测定为例,研究了采用一次性无菌塑料吸管代替牛津杯测定抗生素生物活性的可行性,结果表明:吸管法可以测定抗生素的抑菌谱、最小抑菌浓度、生物效价,克服了牛津杯在反复使用中由于难于清洗造成的抗生素残留与交叉污染问题,方法相对简便、准确,试材来源广泛、价格低廉,可供大中学校师生进行相关生物学教学实验、科学研究时选用。     

多媒体课件在英语口语教学中的应用

随着现代计算机技术的发展,一些计算机技术已经逐渐地被应用于教学过程,有效地对教学起到了辅助作用。多媒体课件在英语口语教学中的应用,使传统教学方式和课堂的枯燥乏味,变得生动活泼,激发了学生的学习兴趣,调动了学生学习的积极性,有效地提高了学生对口语学习的学习能力。     

A Study of Differences between American English and British English in Grammar

This Paper mainly focuses on the Differences between American English and British English in Grammar. It discusses ten aspects of their differences with example（sthat is , differences in the use of certain verbs; differences in the use of articles; differences in the use of prepositions ;the use of subjunctive; tense differences ;the use of collective nouns ;the way of expressing dates; the treatment of a repeated subject after the indefinite pronoun＂one＂; response question; negative form of the first perso...